The present invention relates to a method for producing cyclic chlorophosphazene oligomers, more particularly a method for producing cyclic chlorophosphazene oligomers in a high yield and selectivity, in particular for the trimer and tetramer, by reacting chlorinated phosphorus with ammonium chloride in the presence of a reaction catalyst, while controlling the moisture content of the reaction system, and average particle size and particle size distribution of the ammonium chloride so as to produce minimal amounts of linear compounds.